Patents by Inventor Prabhakara Satyauolu Rao

Prabhakara Satyauolu Rao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7298442
    Abstract: An optical body includes a) first particles comprising a first cholesteric liquid crystal material and b) a second cholesteric liquid crystal material. The first particles and the second cholesteric liquid crystal material form a structure where the first cholesteric liquid crystal material has a pitch that is different than the second cholesteric liquid crystal material. In one example, the second cholesteric liquid crystal material is in the form of second particles. In another example, the first particles are dispersed in a matrix of the second cholesteric liquid crystal material. In other examples, the optical body has more than one layer. In addition, one or more additional cholesteric liquid crystal materials can be used in the optical body. These optical bodies can be used as a reflective polarizer and can be used in a display.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: November 20, 2007
    Assignee: 3M Innovative Properties Company
    Inventors: Christopher C. Bowley, Ikuko Ebihara, Gregory Edward Gilligan, Richard John Pokorny, Marc Dudley Radcliffe, Prabhakara Satyauolu Rao, Philip Edwin Watson
  • Patent number: 6876427
    Abstract: An optical body includes a) first particles comprising a first cholesteric liquid crystal material and b) a second cholesteric liquid crystal material. The first particles and the second cholesteric liquid crystal material form a structure where the first cholesteric liquid crystal material has a pitch that is different than the second cholesteric liquid crystal material. In one example, the second cholesteric liquid crystal material is in the form of second particles. In another example, the first particles are dispersed in a matrix of the second cholesteric liquid crystal material. In other examples, the optical body has more than one layer. In addition, one or more additional cholesteric liquid crystal materials can be used in the optical body. These optical bodies can be used as a reflective polarizer and can be used in a display.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: April 5, 2005
    Assignee: 3M Innovative Properties Company
    Inventors: Christopher C. Bowley, Ikuko Ebihara, Gregory Edward Gilligan, Richard John Pokorny, Marc Dudley Radcliffe, Prabhakara Satyauolu Rao, Philip Edwin Watson
  • Patent number: 6706796
    Abstract: The present invention provides a compound according to the formula: CH2═C(R1)—C(O)—R6—NHCO2(CH2)p(CF2)q—O—((CF2)8CFXO)m(CF2)r—Z wherein each R1 is independently selected from —H, —CH3, —F and —Cl, wherein each R6 is independently selected from substituted or unsubstituted C1-C10 alkyl, cyclic alkyl, or aryl groups, wherein each a is independently selected from 0-3, wherein each X is independently selected from —F, —CF3 or —CF2CF3, wherein each p is independently selected from 1-4, each q is independently selected from 1-5, each r is independently selected from 1-5, each m is independently selected from 1-50, each Z is independently selected from —F and —(CH2)5OH, and each s is independently selected from 1-4. The present invention also provides for the use of this compound as a surfactant in highly fluorinated liquid solvents. Latexes of dispersed particles utilizing this surfactant are provided.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: March 16, 2004
    Assignee: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Naiyong Jing
  • Publication number: 20030092931
    Abstract: The present invention provides a compound according to the formula: CH2═C(R1)—C(O)—R6—NHCO2(CH2)p(CF2)q—O—((CF2)aCFXO)m(CF2)r—Z wherein each R1 is independently selected from —H, —CH3, —F and —Cl, wherein each R6 is independently selected from substituted or unsubstituted C1-C10 alkyl, cyclic alkyl, or aryl groups, wherein each a is independently selected from 0-3, wherein each X is independently selected from —F, —CF3 or —CF2CF3, wherein each p is independently selected from 1-4, each q is independently selected from 1-5, each r is independently selected from 1-5, each m is independently selected from 1-50, each Z is independently selected from —F and —(CH2)sOH, and each s is independently selected from 1-4. The present invention also provides for the use of this compound as a surfactant in highly fluorinated liquid solvents. Latexes of dispersed particles utilizing this surfactant are provided.
    Type: Application
    Filed: September 16, 2002
    Publication date: May 15, 2003
    Applicant: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Naiyong Jing
  • Patent number: 6562889
    Abstract: The present invention provides a stable, non-film-forming dispersion comprising a) dispersed particles, b) a liquid non-polar solvent which is preferably fluorinated, and c) a dispersant selected from the group consisting of highly fluorinated polyethers, having an atomic ratio of carbon to oxygen of between 2 and 4 inclusive, and bearing at least one polar functional group which is preferably an ionizable group such as a carboxylic acid group.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: May 13, 2003
    Assignee: 3M Innovative Properties Company
    Inventor: Prabhakara Satyauolu Rao
  • Publication number: 20030063245
    Abstract: An optical body includes a) first particles comprising a first cholesteric liquid crystal material and b) a second cholesteric liquid crystal material. The first particles and the second cholesteric liquid crystal material form a structure where the first cholesteric liquid crystal material has a pitch that is different than the second cholesteric liquid crystal material. In one example, the second cholesteric liquid crystal material is in the form of second particles. In another example, the first particles are dispersed in a matrix of the second cholesteric liquid crystal material. In other examples, the optical body has more than one layer. In addition, one or more additional cholesteric liquid crystal materials can be used in the optical body. These optical bodies can be used as a reflective polarizer and can be used in a display.
    Type: Application
    Filed: September 21, 2001
    Publication date: April 3, 2003
    Inventors: Christopher C. Bowley, Ebihara Ikuko, Gregory Edward Gilligan, Richard John Pokorny, Marc Dudley Radcliffe, Prabhakara Satyauolu Rao, Philip Edwin Watson
  • Patent number: 6518370
    Abstract: Dispersants that adsorb to hydrophobic particle surfaces in aqueous media are described. The dispersants comprise dendritic polymers having at least one ionizable moiety and at least one peripheral hydrophobic long chain hydrocarbon moiety. Dispersions and inks wherein the dispersant operates as a solitary or co-dispersant are also described.
    Type: Grant
    Filed: May 16, 2001
    Date of Patent: February 11, 2003
    Assignee: 3M Innovative Properties Company
    Inventors: Ahmed Salih Abuelyaman, Prabhakara Satyauolu Rao, Babu N. Gaddam
  • Publication number: 20030018111
    Abstract: The present invention provides a stable, non-film-forming dispersion comprising a) dispersed particles, b) a liquid non-polar solvent which is preferably fluorinated, and c) a dispersant selected from the group consisting of highly fluorinated polyethers, having an atomic ratio of carbon to oxygen of between 2 and 4 inclusive, and bearing at least one polar functional group which is preferably an ionizable group such as a carboxylic acid group.
    Type: Application
    Filed: April 18, 2001
    Publication date: January 23, 2003
    Applicant: 3M Innovative Properties Company
    Inventor: Prabhakara Satyauolu Rao
  • Publication number: 20020132910
    Abstract: The present invention provides a two-step method of making a latex in a highly fluorinated liquid solvent, including a first step of polymerizing together a mixture of: i) 1-2 parts by weight of one or more non-fluorinated free-radically-polymerizable monomers, and ii) 1-9 parts by weight of one or more highly fluorinated macromers terminated at one or more sites with free-radically-polymerizable groups to form a dispersion of seed particles; and a second step of polymerizing together said seed particles with an additional 10-1,000 percent by weight, relative to the total weight of the seed particles, of one or more non-fluorinated free-radically-polymerizable monomers. The present invention additionally provides a fine latex comprising a highly fluorinated liquid solvent and dispersed particles having an average particle size of 250 nm or less and more preferably 200 nm or less. The latexes of the present invention may be useful in an electrophoretic display.
    Type: Application
    Filed: March 11, 2002
    Publication date: September 19, 2002
    Applicant: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Jimmie Rae Baran, Naiyong Jing
  • Patent number: 6452038
    Abstract: The present invention provides a compound according to the formula: CH2═C(R1)—C(O)—R6—NHCO2(CH2)p(CF2)q—O—((CF2)aCFXO)m(CF2)r—Z wherein each R1 is independently selected from —H, —CH3, —F and —Cl, wherein each R6 is independently selected from substituted or unsubstituted C1-C10 alkyl, cyclic alkyl, or aryl groups, wherein each a is independently selected from 0-3, wherein each X is independently selected from —F, —CF3 or —CF2CF3, wherein each p is independently selected from 1-4, each q is independently selected from 1-5, each r is independently selected from 1-5, each m is independently selected from 1-50, each Z is independently selected from —F and —(CH2)sOH, and each s is independently selected from 1-4. The present invention also provides for the use of this compound as a surfactant in highly fluorinated liquid solvents. Latexes of dispersed particles utilizing this surfactant are provided.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: September 17, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Naiyong Jing
  • Patent number: 6395804
    Abstract: Dispersants that strongly adsorb to hydrophobic particles in aqueous media are described. The dispersants comprise one or more polyelectrolyte(s) and further comprise a hydrophobic hydrocarbon moiety. Suspensions and inks comprising the dispersants are also described.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: May 28, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Ahmed Salih Abuelyaman, Babu N. Gaddam
  • Patent number: 6384124
    Abstract: The present invention provides a non-film-forming latex of dispersed particles which may be used in an electrophoretic display, comprising: a) a highly fluorinated liquid solvent, and b) dispersed particles comprising a polymer comprising units according to formula I: wherein each (fcp) is independently selected from highly fluorinated polymer chains and each Q is independently selected from —H and straight or branched non-fluorinated polymer chains (hcp). Latexes of dispersed particles having a very small particle size are especially provided.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: May 7, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Jimmie Rae Baran, Jr., Naiyong Jing
  • Patent number: 6372838
    Abstract: The present invention provides a two-step method of making a latex in a highly fluorinated liquid solvent, including a first step of polymerizing together a mixture of: i) 1-2 parts by weight of one or more non-fluorinated free-radically-polymerizable monomers, and ii) 1-9 parts by weight of one or more highly fluorinated macromers terminated at one or more sites with free-radically-polymerizable groups to form a dispersion of seed particles; and a second step of polymerizing together said seed particles with an additional 10-1,000 percent by weight, relative to the total weight of the seed particles, of one or more non-fluorinated free-radically-polymerizable monomers. The present invention additionally provides a fine latex comprising a highly fluorinated liquid solvent and dispersed particles having an average particle size of 250 nm or less and more preferably 200 nm or less. The latexes of the present invention may be useful in an electrophoretic display.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: April 16, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Jimmie Rae Baran, Jr., Naiyong Jing
  • Publication number: 20010020062
    Abstract: Dispersants that adsorb to hydrophobic particle surfaces in aqueous media are described. The dispersants comprise dendritic polymers having at least one ionizable moiety and at least one peripheral hydrophobic long chain hydrocarbon moiety. Dispersions and inks wherein the dispersant operates as a solitary or co-dispersant are also described.
    Type: Application
    Filed: May 16, 2001
    Publication date: September 6, 2001
    Applicant: 3M Innovative Properties Company
    Inventors: Ahmed Salih Abuelyaman, Prabhakara Satyauolu Rao, Babu N. Gaddam
  • Patent number: 6262207
    Abstract: Dispersants that strongly adsorb to hydrophobic surfaces of particles in aqueous media are described. The dispersants comprise a hydrophilic or amphiphilic polymer chain containing ionizable moieties and having a terminal forked hydrophobic segment. Suspensions and inks comprising the dispersants are also described.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: July 17, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: Prabhakara Satyauolu Rao, Ahmed Salih Abuelyaman, Babu N. Gaddam
  • Patent number: 6258896
    Abstract: Dispersants that adsorb to hydrophobic particle surfaces in aqueous media are described. The dispersants comprise dendritic polymers having at least one ionizable moiety and at least one peripheral hydrophobic long chain hydrocarbon moiety. Dispersions and inks wherein the dispersant operates as a solitary or co-dispersant are also described.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: July 10, 2001
    Assignee: 3M Innovative Properties Company
    Inventors: Ahmed Salih Abuelyaman, Prabhakara Satyauolu Rao, Babu N. Gaddam